Tim Adye Objectivity Export Tools Meeting Summary
Detailed summary of the 15th February 2000 meeting regarding ongoing work, future plans, and concerns about Objectivity export tools. Updates on redesign using Java/JNI, database maintenance, and future exports discussed.
Tim Adye Objectivity Export Tools Meeting Summary
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Presentation Transcript
Data Distribution Tim Adye Rutherford Appleton Laboratory BaBar Collaboration Meeting 15th February 2000 Tim Adye
Objectivity Export Tools Exports KanGA Export Techniques Bulk exports Tim Adye
Objectivity Export Tools • Book-keeping database up and running (Teresa Barillari) • Maintains a catalogue of exports • Accessible from the web • Red Queen’s race to maintain 2 Gb file support in the latest releases (Dominique Boutigny, TJA) • 8.2.x OK. • Problems with 8.3.x – 8.4.x . • 8.5.x (+ BdbAccess tag) OK • Large (>2 Gb) file exports (TJA) • SLAC/IN2P3 staging has 2 Gb limit • Workaround implemented Tim Adye
Objectivity Export Tools -ongoing work • Use collection database (colldb) (Moreno Marzolla, Artem Trunov) • Replace (slow) Objectivity Federation scan with (fast) Oracle query • HPSS support (TJA) • Bypass disk-resident Federation • Maybe faster. Maybe slower. • Reduce impact on/from other users • Being tested. • Graphical User Interface (Cristina Bulfon) • Simplifies export/import process • First version looks good! • Needs work for production use Tim Adye
Objectivity Export Tools -The Next Generation • Redesign of BdbDistTools using Java/JNI being investigated (Jean-Noel Albert and Yemi Adesanya) • Present design is quite byzantine • Perl, TCL, sh, C++ • Continue with present tools in parallel Tim Adye
Objectivity Exports from SLAC • Dominique Boutigny and Cristina Bulfon have continued making regular exports to IN2P3, RAL, and CASPUR. • ~1 export / 2 weeks • Analysis and SP2 mini/micro data • No digis or reco data • isPhysicsEvents and Analysis Working Group (AWG) skims Tim Adye
Future Objectivity Exports • Last export 811 Gb on 17 DLTs • If this continues, will very soon overwhelm regional centres • Propose to • Stop export of ESD (“miniDST”) • not currently usable • Suspend export of AWG skims • Need to understand why these are so large • One large component (AIO) can probably be dropped immediately Hopefully this will reduce future exports by a factor of 3. Tim Adye
KanGA Exports Tim Adye
KanGA Exports • Exporting KanGA(née NOTMA) from SLAC is much simpler than Objectivity • Ordinary Unix files and directory structure • Only network transfers so far • Eg. SLAC -> RAL -> CASPUR • Full 25 Gb EventStiore • Greatly simplified by mirroring tool, rsync • Any site with sufficient network bandwidth can use this now • See Data Distribution web page for details Tim Adye
KanGA Tape Export • Still need to develop tape export tools • Catalogue what’s been transferred • Handle SLAC/IN2P3/direct tape access • Initial version will be based on existing BdbDistTools • Already does much of the same job • Use same sort of catalogue • TDF and web Tim Adye
DLT Drive • Currently all DLT exports via DLT stacker • Single drive; only 39 slots • attached to tapeserv2 • New DLT robot awaiting installation • 3 drives; 300 slots • will be directly attached to our export machine, datamove3 Tim Adye
Bulk KanGA Exports • Won’t do bulk KanGA export before reprocessed data is available • 2nd half of March • Export all reprocessed KanGA data • Bulk exports on DLT-7000 only • IN2P3 excepted: Redwood/Eagle • Invite expressions of interest to receive bulk KanGA tape exports Site requirements:- • DLT-7000 drive • NB. Not DLT-4000 • Own DLT tapes (~$64/tape) • Sufficient disk space (>100 Gb?) • Manpower to make imports Tim Adye
Bulk KanGA Exports • Encourage some groups to “share” tapes • DLTs sent from one institute to another • Less work overall • Cheaper (tapes, postage) • Groups must coordinate • Some won’t get data as rapidly • Could still use network copy from nearby institute • Requires very good network connection • Still require manpower and disk space Tim Adye
Bulk KanGA Exports • Let me know if you want to receive bulk KanGA export:- • Contact me directly or speak up at CCG Meeting • What sort of export? • DLT or network? • Is there anyone else you can share with? Tim Adye